Tabulating mechanism



April 8, 1941.

W. W. LASKER TABULA'IING MECHANI SM Filed July 31, 1937 15 Sheets-Sheet l INVENTOR W.W.LA$KER,oEcEAsEo W.W.LA$KER,JR.,EXECUTOR BY AT ORNEY April 8, 1941. w. w. LASKER TABULATING MECHANISM Filed July 31, 1937 15 Sheets-Sheet 2 FIG 3 Fl G. 2.

FIG I INVENTOR w.w L ASKER, DECEASED W.W. LA 5 KER,JR.,EXECU TOR BY T1 RNEY April 1941- w. w. LASKER 2.237.908

TABULATING MECHANISM Filed July 31, 1937 15 Sheet's-Sheet 5 INVENTOR W.W. LASKER,DECEASED w. W. LA SKER,JR.,E Ecu'roR BY A TORNEY April 1941- w. w. LASKER I 2.237.908

TABULATING MECHANISM Filed July 31, 1937 15 Sheets-Sheet 4 W.W'LASKER.,DECEASED W.W. LASKER,JR.,ExEcu TOR April 8, 1941. w. w. LASKER TABULATING MECHANISM Filed July 31, 1957 15 Sheets-Sheet 5 mnN . QOE

INVENTOR W. W LA$KER,DECEA.SED W. W. LASKER.,JR. EXECUTOR BY A ORNEY April w. w. LA SKER I 2.237.908

' TABULATIIYJG MECHANISM Filed July 31, 1937 15 Sheets-Sheet 3 Flcf/i NVE N TOR W. w.' LAS KER DECEASED W.W. LA$KER,JR.,l-:xEcuToR w. w. LASKER 2.237.908

TABULATING MECHANiSM Filed July 31, 1937 15 Sheets-Sheet 7 mm ATT RNEY W. W. LASKER, DECEASED w. w. LASK ER V TABULATING MECHANISM April 8, 1941.

15 Sheets-Sheet-B Filed July 31, 1937 Y INVENTOR w.w. LASKER, W.W.LASKER,JR.

DECEASED ,EXECUTOR A TORNEY April 1941- w. w. LASKER 2.237.908

' TABULATING MECHANISM Filed July 31, 1937 15 Sheets-Sheet 1o FIGIB.

OOOGQOO OOOOOO O0OOO-' INVENTOR W. W. LASKER DECEASED W.W. LASKER,JR.,Exzcu'roR By AT RNEY April 8, 1941. w. w. LASKER TABULATING MECHANISM Filed July 31, 1937 15 Sheets-Sheet l1 INVENTOR Wvw. LASKER DECEASED W.W. LASKER,JR.,ExEcuToR AT ORNEY April 8, 1941. w. w. LASKER TABULATING MECHANISM M15 Sheets-She et 12 Filed July 31, 1937 FIG.|8.

FIG. I7.

INVENTOR w.w. LASKER, DEC-EASED W.W. LASKER,J

R EXECUTOR ORNEY April 1941- w. w. LASKER 2.237.908

I TABULA'IING MECHANISM v 15 Sheets-Sheet 15 i Filed July 51, 1937 INVENTOR W. W. LASKER. DECEASED W.W. LASKER,JR., EXECUTOR A ril 8, 1941. w. w. LASKER TABULATING MECHANISM Filed July 31, 1937- 15 Sheets-Sheet 14 BY ATTOR Y Patented Apr. 8, 1941 TABULATING MECHANISM William W. Lasker, deceased, late of Brooklyn, N. Y, ,by William W. Lasker, Jr., executor,

Brooklyn, N. Y., assignor to Remington Rand !nc., Buflalo, N. Y., a corporation of Delaware Application July 31, 1937, Serial No. 156,692

Claims.

This invention relates to record card controlled tabulating machines and particularly to total taking control mechanisms therefor.

This application is a continuation in part of copending application of W. W. Iasker, S. N. 684,438, filed August 8, 1933, now Patent No. 2,185,258, dated January 2, 1940, and is a further development of the total taking control mechanism disclosed in the patent to W. W. Lasker, No. 2,044,119, issued June 16, 1936.

The principal object of this invention is to provide a control mechanism for controlling machine functions during total taking operations initiated by changes in the group designation of successive records, and for controlling machine functions during grand total taking operations initiated by changes in grand group designations.

Another object of the invention is to provide means for effecting successive total taking operations without the use of control cards.

Another object of the invention is to provide a control mechanism for effecting successive total taking operations upon a change in grand group designation, in the first of which a total is taken from one accumulator, in the second, a grand total is taken from another accumulator.

Another object of the invention is to provide means to shift from group total control to grand total control during successive operations of the control mechanism.

Another object of the invention is to provide means to prevent successive operations of the control mechanism when a group total is taken.

Other objects of the invention are disclosed in the course of the specification.

One embodiment of the invention is illustrated in the accompanying drawings, in which,

Figs. 1, 2, and 3 represents a conventional sectional elevation through a typical Powers tabulator equipped with the invention,

Fig. 4 indicates the manner in which Figs. 1, 2, and 3 are arranged,

Fig. 5 is a left side elevation of the tabulator of Figs. 1, 2, and 3 with portions of the framework removed,

Figs. 6 and 7 represents an exploded isometric view of the total taking control mechanism and the associated mechanisms,

Fig. 8 indicates the manner in which Figs. 6 and 'l are arranged,

Fig. 9 is a sectional isometric view of the reading retaining mechanism and the change of designation sensing mechanism,

Fig. 10 is a sectional isometric view of the zero stop depressor mechanism,

Fig. 11 is a right side sectional elevation of a portion of the rear accumulator timing mechanism,

Fig. 11A is a right side view of a portion of the timing mechanism for the rear accumulator,

Fig. 12 is a schematic sectional view of the credit balance mechanism and the mechanism for controlling the designating type carrier,

Fig. 13 is a plan view of the total taking control mechanism,

Fig. 14 is a left side elevation of the total taking control mechanism,

Fig. 15 is a rear elevation of the actuating mechanism for the total taking control mechanism,

Fig. 16 is a fragmentary sectional elevation of the card feeding mechanism and the controls therefor,

Fig. 17 is a fragmentary sectional elevation of the card stop mechanism and the control therefor,

Fig. 18 is a fragmentary sectional elevation of the retract mechanism and controls for the reading retaining mechanism,

Fig. 19 is a fragmentary sectional elevation of control mechanism taken along lines 24-24,

25-25, 2626, respectively, of Fig. 13.

Figs. 27 and 27A, taken together, form a timing chart.

In Patent No. 2,044,119 a total taking control mechanism isdisclosed that is arranged to control total taking operations in a tabulator having one or more group total accumulators. This control mechanism operative upon a change of designation in successive records, is adapted to vary the normal tabulating functions of the machine and to control the sequence of operations necessary for taking a total in the Powers tabulator. For this purpose, the control mechanism operates through three steps to control first, a conditioning cycle in which the accumulator transfer mechanisms are normalized, second, a total taking cycle in which the group total is rolled out of the accumulator, and third, a normalizing cycle in which the control mechanism is restored to rest position and the data in the new card is tabulated. In patent of W. W. Lasker No. 2,066,406, issued January 5, 1937, the same control mechanism is adapted to control total taking and grand total taking operations in a tabulator equipped with the familiar Powers direct subtraction and grand total mechanism similar to that originally disclosed in co-pending application of W. W. Lasker et a]., S. N. 535,842, filed May 8, 1931, now Patent No. 2,124,177, dated July 19, 1938. In a tabulator of this type, the items that comprise each group are entered into a group total accumulator during accumulating cycles, the totals of each group are transferred to a grand total accumulator during total taking operations, and the grand total of a plurality of groups are taken from the grand total accumulator during grand total taking operations. In this arrangement, the control mechanism operates as in Patent No. 2,044,119 during total taking operations, however when a grand total is to be taken, the last group total must be transferred to the grand total accumulator prior to the taking of the grand total. Therefore, to effect the operations that comprise a grand total taking operation two control cards are inserted in the card pack at the point where a grand total is required. The first control card initiates the operation of the control mechanism thereby causing the last group total to be taken and is then, ejected. The second control card initiates a second operation of the control mechanism and at. the same time shifts its control to the grand total accumulator thereby causing the grand total to be taken. The total taking control mechanism of the present invention is arranged to control both total taking and grand total taking operations upon changes in group and grand group designations, respectively, and in each case, to retain the new card in the card chamber throughout the operation in-.

itiated thereby, so that the data contained therein may be tabulated in the succeeding accumulating cycle.

Although total taking control mechanisms, based upon the principle disclosed herein, may be constructed for any type of tabulating machine in which successive totals are to be taken, the device shown herein is applied to a well known form of Powers tabulator in which it is particularly adapted to operate.

In the embodiment shown in the drawings, a form of the present invention is applied to a tabulating machine having a computing mechanism similar to that disclosed in Patent No. 2,124,177, and containing certain modifications disclosed in Patent No. 2,066,406. The base mechanism of this machine comprises driving mechanism, card feeding mechanism and card sensing mechanism that is substantially the same as that disclosed in Patent No. 2,044,119, and includes a change of designation sensing mechanism and reading retaining mechanism that are similar to those disclosed in copending application of W. W. Lasker, S. N. 656,233, filed February 11, 1933, now Patent No. 2,151,406, dated March 21, 1939. Powers tabulating machines, containing the above mentioned mechanisms, are being regularly manufactured and have been in general commercial use for several years. Therefore, a brief description of the manner of operation of these mechanisms will suffice for the purposes of the present disclosure. To facilitate the understanding of the mechanisms involved, the specification has been divided into three major headings, namely, Base mechanism, Computing mechanism, and Total taking control mechanism.

Throughout the specification it will be understood that all shafts, levers, and movable parts generally are supported on or carried by the main framework of the machine, even though such is not specifically shown or mentioned. All links and link-like elements will be considered as piv otally connected to the associated elements unless otherwise specifically stated. Many elements consist of two parts joined together for the purpose of assembly or adjustment. more, many of the arms are provided with keyways, set screws, or friction clamps for corresponding adjustments. In general, such construction is not shown, for to do so would unnecessarily complicate the drawings. Many elements, for example the several total shafts, have oscillatory movements. Suitable limit stops are provided therefor to prevent over-running, or under-running, or both. Such stops will not be further mentioned or described for their existence will be tacitly assumed. In many instances spring clips, cotter pins, enlarged or riveted heads, or other fastening devices are omitted from both the drawings and the detailed description. Unless otherwise specifically mentioned, the expression mounted on, as applied to arms, cams, etc., connotes that the element is "fixed on" or "rigidly connected to the associated shaft. The terms forward, rearward," "upper, lower, right, "left," and their grammatical variations occur throughout this specification. These terms refer to the relative locations of the parts as viewed from the front of the machine. Thus, forward-always means to the left in Figs. 1-3, inclusive, whereas rearward means to the right. The adoption of these conventions will considerably shorten the detailed description without detracting from the clarity of the described mode of construction and operation. Furthermore, certain of the expressions frequently used herein, although well known in the art. are defined for the sake of clarity, as follows:

ords to be tabulated, comprising one or more groups of record cards.

Group designation-the designative data common to all of the cards of a group.

Grand group designation-the designative data common to all of the cards of a grand group.

Group total (or, total)the total of the quantitative data contained in all the cards of a group.

Grand group total (or, grand total) the total of 'the quantitative data contained in all the cards of a. grand group.

Group total conditioning cycle (or, total conditioning cycle)the cycle in which the machine is conditioned for yielding a group total.

Group total taking cycle (or, total takin cycle) the cycle in which the group total accumulator is cleared and the group total printed on the report sheet. In addition, in the present instances, the group total is transferred to the grand total accumulator, and the total taking control mechanism is normalized.

Further- Group total taking operation (or, total taking operation)the entire sequence of cyclical operations, involved in the taking of a group total, which is initiated as the result of the sensing of a change in group designation. In the present instance a group total taking operation comprises:

1, a group total conditioning cycle, and

2, a group total taking cycle.

Grand group total taking operation (or, grand total taking operation)the entire sequence of cyclical operations, involved in the taking of a grand group total, which is initiated as the result of the sensing of a change in grand group designation. In the present instance, a grand group total taking operation comprises:

1, a group total conditioning cycle,

2, a group total taking cycle,

3, a grand group total conditioning cycle,

and

4, a grand group total taking cycle.

Base mechanism The operations of the tabulator are controlled from a main drive shaft I (Figs. 1, 5, 6, 7 which is driven by an electric motor (not shown), controlled by switch H, and is connected thereto by means of a clutch (not shown), mounted on rock shaft :2 controlled by a clutch operating mechanism generally designated by reference character l3 (Fig. which is similar in function and operation to that disclosed in Patent No. 2,044,119, the arrangement being such that a cycle of operation is completed during each revolution of shaft to. As described in said patent, the clutch mechanism is so arranged that when the machine is stopped it is always stopped at a given point in a cycle. The point selected is one at which the several machine elements are in such position that the operator may conveniently perform any required manual operation such as the insertion of a new translator, the insertion of a new report sheet, the resetting of the change of designation sensing mechanism, etc. This condition occurs when shaft l0 (Fig. 1) is rotated to a position in which the keyway therein is in its top dead center position, as shown in the drawings, and is referred to as the normal or stopping position of the machine. Thus, for the purposes of this description, each machine cycle begins when the keyway in shaft l0 moves counter-clockwise from its dead center position, and fends" when the keyway is returned thereto.

Record cards placed in card magazine l4 (Figs. 1 and 2) are successively passed, by means of picker knife I5 to feed rolls l 6 which convey them to card sensing chamber I1. Each card is retained in the card chamber by card stop 18 during the period in which it is sensed by spring urged sensing pins l9, mounted in reciprocable pin box 20, and then, is passed by the usual skid rolls (not shown) to eject rolls 2| by which it is conveyed to receiving magazine 22.

Picker knife l5 of the card feeding mechanism (Figs. 1, 6, 7, 16) is connected to arm 23 mounted on rock shaft 24 and is operated, through arm 25, link 26, arm 21 and follower 28, by card feed cam 30 mounted on shaft Ill. The arrangement is such that the card feeding mechanism is operated once during each cycle of operation'and is held retracted by cam 30 when the machine is in its normal or stopping position, as shown in the drawings (see Fig. 2'7, line 2, cycle A) The sensing pin box 20 (Fig. 1) is provided with a plurality of rows of spring pressed pins l9, arranged to register with the perforation positions in the record cards, and is reciprocated during each cycle of operation by a pair of eccentrics 3| mounted on shaft 10. The arrangement of eccentrics 3| being such that, in the normal or stopping position of the machine, the pin box is raised to its highest position (see Fig. 27, line 1, cycle A). Each row of sensing pins is provided with the usual locking slide 32 arranged to lock the pins in elevated position when they have passed through perforations in a card. The usual mechanism, similar to that disclosed in Patent No. 2,044,119 and indicated herein by lever 33, is provided to prevent the operation of slides 32 when there is no card in chamber l'l.

Card stop l8 (Figs. 1, 2, 6, 7, 17) is operated in the usual manner, through lever 34, link 35, arm 36, shaft 31, arm 38, and link 39, by card stop cam 40 mounted on shaft H). The arrangement is such that card stop i8 is operated once during each cycle of operation, and is held in effective position by cam 40 when the machine is in its normal or stopping position (see Fig. 27, line 3, cycle A).

Mounted in the frame of the machine above the sensing pin box is an intermediate pin box mechanism (Figs. 2, 7, 9) having the same function as the corresponding mechanism in Patent No. 2,044,119, namely, to retain the set-up contained in the record cards and to sense changes in the designation data in successive cards. The intermediate pin box mechanism shown in the drawings has been modified in the manner disclosed in Patent No. 2,151,406 to permit the use of the well-known Powers ninety column card and to permit different types of totals to be taken when different types of designation changes are sensed.

This mechanism comprises a box like structure 4| provided with a plurality of rows of spring pressed pins 42 arranged to register with sensing pins IS. The springs associated with pins 42 are stronger than thesprings associated with pins I9, as in Patent, No. 2,044,119, so that, in the event pin box 20 is elevated when there is no card in chamber l1, pins I9 are held down and do not elevate stops in the computing units. The sets of pins in each column, that correspond to the upper and lower zones of a record card, are each provided with a locking slide 43 that is urged rearwardly by spring 44. A plurality of locking faces on each slide 43 cooperate with studs on the associated pins 42 (Figs. 6 and 7) to hold the pins in raised position when elevated by sensing pins l9. Locking slides 43 are retracted, in the manner and for the purpose described in Patent No, 2,044,119, during the period in which pins 42 are held up by pins I9, by means of bail 45, rock shaft 46, arm 41, push rod 48, arm 49, and retract cam 50, mounted on shaft H) (see Fig. 27, line 4, cycle A). Retraction of slides 43 releases all pins 42 that were elevated under control of the preceding card and permits them, unless held up due to a corresponding perforation in the new card, to be moved to their lower position by the associated springs.

The change of designation sensing mechanism includes a plurality of cam slides 5| (Figs. 2, 7, 9) arranged in a manner similar to locking slides 53, that is, a cam slide 5| being provided for each set of pins 42 that correspond to each column of perforation positions in the record cards. A plurality of camming faces on each slide 5| coact with studs on the associated pins 42, the arrangement being such that any change in the setting, that is, the raising or lowering, of a pin 42 in any column serves to move the associated slide 5| forwardly (to the left in Fig. 2). The movement of slides 5| is utilized, in the manner described in Patent No. 2,151,406, to initiate the operation of the total taking control mechanism. For this purpose, a plurality of variably settable keys 52 (Figs. 2, 7, 9, 13), one for each cam slide 5|, are slidably mounted on transverse comb in its upper position, movement of slide 5| is ineffective thereon. When key 52 is placed in its intermediate position, as indicated at 52T of Fig. 7, interponent 54 is moved between the end of slide 5| and a bail rod 55 that is supported by arm 56 mounted on a rock shaft 51. Under these circumstances, movement of slide 5| serves to rock shaft 51 to initiate the operation of the total taking control mechanism as will be described hereinafter. When key 52 is placed in its lower position, as indicated at 52G of Fig. 7, interponent 54 maintains an operative relationship between slide 5| and ball rod 55 and, in addition, a shoulder on the interponent establishes contact with a second bail rod 58 that is supported by arms 59 mounted on rock shaft 60. Under these circumstances, movement of slide 5| serves to rock shaft 51 to initiate the operation of the total taking control mechanism and, in addition, serves to rock shaft 60 to initiate the operation of additional control mechanism, hereinafter described, which causes a repetition of the operation of the total taking control mechanism, and, at the end of the first total taking operation varies the control of the total taking control mechanism, which is normally arranged to cause totals to be taken from the total accumulators, to cause the total to be taken from the grand total accumulator.

Thus, when a total is to be taken upon a change of designation in a given column, key 52, corresponding to that column, is set in its intennediate position; whereas, when a grand total is to be taken upon a change of designation in another column, key 52, corresponding to that column, is set in its lower position. Keys 52 that correspond to the remaining columns are then set in their upper positions so that the movements of the associated slides 5| are ineffective.

The movements of pins 42 are transmitted to the computing mechanism, in the usual manner, by translator wires 55 (Fig. 2) slidably mounted in a removable translator frame 65.

Computing mechanism By way of illustration, the mechanism of the present invention is shown in conjunction with the familiar Powers direct subtraction and grand total mechanism, the function and manner of operation of which is fully disclosed in Patent No. 2,124,177 and embodies certain modifications disclosed in Patent No. 2,066,406. This mechanism comprises a rear accumulator arranged to accumulate positive and negative amounts and a front accumulator arranged to accumulate grand totals of the totals taken from the rear accumulator. The arrangement is such that the front accumulator is conditioned to non-add during accumulating operations so that the quantitative data taken from the record cards is entered only in the rear accumulator. total is taken from the rear accumulator, the front accumulator is conditioned for an adding operation so that the total taken from the rear accumulator is transferred to the front accumulator during the total taking operation. When a grand total is to be taken, the total of the last group of items is transferred to the front, and then, the grand total is taken therefrom. Grand total taking is completed during a series of operations, in the first part of which, the rear accumulator is conditioned for total taking and the front accumulator is con ditioned for accumulating to effect the necessary transfer. In the latter part of the series of operations, the front accumulator is conditioned for total taking, whereby the grand total is printed and the rear accumulator is conditioned for a non-adding operation to prevent an improper transfer of the grand total. The mechanism for performing these functions is being regularly manufactured and has been in general commercial use for several years. Therefore, a brief description thereof is sufficient for the purposes of the present disclosure. To avoid unnecessary repetition, only a single computing section, comprising a front accumulator and a rear accumulator and the several controls therefor, has been shown in the drawings. It is to be understood that any suitable number and type of computing sections may be added, as described in Patent No. 2,066,406 and Patent. No. 2,124,177 to form a complete machine according to the particular type of accounting problem that is to be handled.

The several mechanisms in the computing section are controlled primarily by a drive shaft ll (Fig. 3) which is driven by base drive shaft ll (Fig. 1) through an arrangement of bevel gears and an inclined shaft 1| as in Patent No. 2,066,406 so that shaft [0 makes a complete revolution for each revolution of shaft I0. The rotary movement of shaft 10 is converted, by means of crank I2, link 13, and arm 14 (Fig. 5) to impart oscillating movement, during each cycle of operation, to rock shaft 15 on which is mounted the usual fan cam 16 (Fig. 3) that forms a part of the timing mechanism of the front accumulator. Fan cam 15 also controls the oscillating movement of the type carriers by means of link Il connected to an arm 18 that is provided with a bean-shaped cam slot for a follower roller on the type carrier restoring bail I9. The arrangement of bail I9 is such that it retains type carriers 80, and thereby the associated gear sectors 8|, in their rearward position during the period in which digit stops are being raised by the sensing mechanism.

The mechanism for positioning type carriers (Fig. 3) consists of the usual Powers, ninetycolumn stop basket, similar in function to an earlier form disclosed in patent to W. W. Lasker, No. 1,780,621, issued November 4, l936,'that consists of a plurality of columns of stop elements.

When a each column comprising a nine stop 82, four digit stops 83 and a zero stop 84 which are adapted to engage a heel on gear sector 8|. The arrangement is such that elevation of any stop 82 or 83 serves to position type carrier 88 for printing the corresponding odd digit, whereas the elevation of a stop 83 in conjunction with nine stop 82 serves to position the type carrier for printing the next higher even digit. Stops 82 and 83 are provided with the usual stud that cooperates with a cam face on slide 85 so that the elevation of any digit stop serves to move slide 88 rearwardly (to the right in Fig. 3), against an ear on spring urged bell-crank 86, to lower. or hold lowered, the zero stop 84 whereby type carrier 88 is freed to move forwardly.

In order to relieve a portion of the load that is placed on a translator wire 85 in raising a digit stop and simultaneously lowering the zero stop, additional means are provided for lowering all zero stops 84 during each cycle of operation. This mechanism comprises a zero stop depressor cam 98 (Figs. 10, 12) mounted on shaft 18 which actuates an arm 9I, pivotally mounted on the rear grand total shaft I60, provided with teeth that cooperate with a toothed arm 92 fast on the rear total shaft I48. Also mounted on rear total shaft I45 is a linger 93 that underlies a stud in a ball 94 that cooperates with the vertical arms of hell cranks 86 to which the zero stops are resiliently connected. When the roller on arm 9| rides onto the high dwell of cam 98, bail 94 is rocked counter-clockwise thereby rocking bell-cranks 86 counter-clockwise to lower zero stops 84. Cam 98 serves to depress the zero stops during the period in which the digit stops are raised by the translator wires and to release the zero stops prior to the time that restoring bail 19 moves forwardly. Thus, if a digit stop is raised in a given column, slide 85 holds the zero stop depressed after the follower on arm 9| rides off the high dwell on cam 98 so that the type carrier may move forwardly when restoring ball 19 is released; whereas, if a digit stop is not raised, the zero stop is elevated by the spring on bell-crank 88 before the restoring ball is released and serves to hold the type carrier in its rearward position.

Rear accumulator The rear accumulator mechanism shown in the drawings (Figs. 3 and 12) is the usual Powers direct subtraction mechanism comprising an accumulator I80 supported by links I8I, a plurality. of adding racks I82 for inserting positive amounts in the accumulator, and a plurality of subtracting racks I83 for inserting negative amounts in the accumulator, each set of racks being joined by a spring and pin-in-slot connection to a forked link I84 which is in turn connected to type carrier 88. Accumulator I88 is provided with ball I85 mounted on links I" for locking the accumulator wheels in stationary position when disengaged from the actuating racks, mechanism for effecting transfers from each accumulator wheel to the adjacent wheel of higher order, means controlled by cam I88 on shaft 18 for restoring tripped transfer pawls during the period in which the actuating racks I82, I83 are moved forwardly, and a closed cycle carrying mechanism indicated by levers I81, for

inserting the fugitive one when the accumulator passes through zero, all as disclosed in Figs. 2 and 3 of Patent No. 2,066,406.

The mechanism for causing the engagement subtracting racks and disengagement of accumulator I88 and its actuating racks is also the same as that disclosed in Patent No. 2,066,406. This mechanism includes a pair of spring urged centering arms I88 that serve to shift the accumulator to a middle or disengaged position unless otherwise controlled. A T-shaped link I89, connected to an arm I89A pivotally mounted on a rock shaft H8, is urged rearwardly by a strong spring III and is normally engaged, bymeans of spring H3 and lever II4, with an upper stud on a T- shaped lever H2, pivotally mounted at Hi, to cause the engagement of the accumulator with adding racks I02. When an item is to be sub-' tracted, a special perforation in the card causes lever II 4 to be rocked clockwise to engage link I89 with the lower stud on lever H2 and thereby cause the engagement of accumulator I88 with I83. During accumulating cycles, the usual timing mechanism (Fig, 11) which is mounted on the extreme right side of the machine and comprises cam I28 mounted on shaft 18, bell-cranks I2I and I22, pitman I23 which is held in engagement with bell-crank I2I during accumulating cycles by arm I24 on rock shaft I25, and arm I26 mounted on shaft 8', serves to rock shaft II8 clockwise. The movement of shaft II8, through an arm II8A mounted thereon and a stud I89B on arm I89A, serves to shift pitman I89 forwardly against the tension of spring III to permit the disengagement of the accumulator immediately prior to the time at which the actuating racks move forwardly and to effect the engagement of the accumulator immediately prior to the time at which the actuating racks are returned.

When a total is to be taken from the rear accumulator, means hereinafter described vary the normal accumulating timing of the machine so that the last accumulating cycle is followed by a conditioning cycle and then a total taking cycle. During the conditioning cycle the accumulator transfer mechanism is returned to normal position and, in addition, the accumulator is conditioned for engagement with either the adding racks I02 or the subtracting racks I83 in accordance with the characteristic of the total standing thereon. This latter function is performed by the credit balance mechanism, as fully disclosed in Patent No. 2,066,406, which comprises a pivotally mounted controller I38 (Fig.

3), operable by either one of the levers I81 of the closed cycle carrying mechanism, and a link I3I connected to leverII4, an arm I32 capable of coacting with a stud I33 on link I3I and mounted on a credit balance rock shaft I35 which is rocked during the conditioning cycle. The arrangement is such that when-the characteristic of the total standing on accumulator I88 passes from negative to positive, lower lever I81 rocks controller I38 counter-clockwise to shift stud I33 out of the path of movement of the arm I32 and thereby permits spring III to condition the accumulator for engagement with racks I82, as in adding operations, whereas, when the characteristic of the total standing on 1 accumulator I88 passes from positive to negative, upper lever I81 rocks controller I38 clockwise to shift stud I33 into the path of movement 

